<!DOCTYPE html>
<html>

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <link rel="stylesheet" href="../../index.css">
    <script src="https://unpkg.com/canvaskit-wasm@latest/bin/canvaskit.js"></script>
    <script src="../dist/iife/spine-canvaskit.js"></script>
    <style>
        * {
            margin: 0;
            padding: 0;
        }
    </style>
</head>

<body class="p-4 flex flex-col items-center">
    <h1>CanvasKit Example</h1>
    <canvas id=foo style="margin: 0 auto; width: 600px; height: 400px;"></canvas>
</body>

<script type="module">
    // Function to read file contents from a path, used to load texture atlas and skeleton file.
    async function readFile(path) {
        const response = await fetch(path);
        if (!response.ok) throw new Error("Could not load file " + path);
        return await response.arrayBuffer();
    }

    // Ensure we render at full DPI.
    const canvasElement = document.querySelector("#foo");
    const dpr = window.devicePixelRatio || 1;
    canvasElement.width = canvasElement.clientWidth * dpr;
    canvasElement.height = canvasElement.clientHeight * dpr;

    // Initialize CanvasKit and create a surface from the Canvas element to draw to
    const ck = await CanvasKitInit();
    const surface = ck.MakeCanvasSurface('foo');

    // Scale the CanvasKit coordinate system
    surface.getCanvas().scale(dpr, dpr);

    // Load the texture atlas
    const atlas = await spine.loadTextureAtlas(ck, "/assets/spineboy.atlas", readFile);

    // Load skeleton data
    const skeletonData = await spine.loadSkeletonData("/assets/spineboy-pro.skel", atlas, readFile);

    // Create a drawable and scale and position the skeleton
    const drawable = new spine.SkeletonDrawable(skeletonData);
    drawable.skeleton.scaleX = drawable.skeleton.scaleY = 0.4;
    drawable.skeleton.x = 300;
    drawable.skeleton.y = 380;

    // Set the "hoverboard" animation on the first track of the animation state.
    drawable.animationState.setAnimation(0, "hoverboard", true);

    // Create a skeleton renderer to render the skeleton with to the canvas
    const renderer = new spine.SkeletonRenderer(ck);

    let lastTime = performance.now();
    // Rendering loop
    function drawFrame(canvas) {
        // Clear the canvas
        canvas.clear(ck.Color(52, 52, 54, 1));

        // Calculate the time that's passed between now and the last frame
        const now = performance.now();
        const deltaTime = (now - lastTime) / 1000;
        lastTime = now;

        // Update the drawable, which will advance the animation(s)
        // apply them to the skeleton, and update the skeleton's pose.
        drawable.update(deltaTime);

        // Render the skeleton to the canvas
        renderer.render(canvas, drawable);

        // Request the next frame
        surface.requestAnimationFrame(drawFrame);
    }
    surface.requestAnimationFrame(drawFrame);
</script>

</html>